Food additive

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The different forms of emulsifier lecithin - powder, two different concentration liquids, granular and powder lecithin Lecithin-Formulierungen.jpg
The different forms of emulsifier lecithin – powder, two different concentration liquids, granular and powder lecithin

Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salting), smoke (smoking), sugar (crystallization), etc. This allows for longer-lasting foods such as bacon, sweets or wines. With the advent of ultra-processed foods in the second half of the twentieth century, many additives have been introduced, of both natural and artificial origin. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process, through packaging, or during storage or transport. [1] [2]

Contents

Numbering

To regulate these additives and inform consumers, each additive is assigned a unique number called an "E number", which is used in Europe for all approved additives. This numbering scheme has now been adopted and extended by the Codex Alimentarius Commission to internationally identify all additives, [3] regardless of whether they are approved for use.

E numbers are all prefixed by "E", but countries outside Europe use only the number, whether the additive is approved in Europe or not. For example, acetic acid is written as E260 on products sold in Europe, but is simply known as additive 260 in some countries. Additive 103, alkannin, is not approved for use in Europe so does not have an E number, although it is approved for use in Australia and New Zealand. Since 1987, Australia has had an approved system of labelling for additives in packaged foods. Each food additive has to be named or numbered. The numbers are the same as in Europe, but without the prefix "E".[ citation needed ]

The United States Food and Drug Administration (FDA) lists these items as "generally recognized as safe" (GRAS); [4] they are listed under both their Chemical Abstracts Service number and FDA regulation under the United States Code of Federal Regulations.

Categories

Food additives can be divided into several groups, although there is some overlap because some additives exert more than one effect. For example, salt is both a preservative as well as a flavor. [5] [1]

Acidulants
Acidulants confer sour or acid taste. Common acidulants include vinegar, citric acid, tartaric acid, malic acid, fumaric acid, and lactic acid.
Acidity regulators
Acidity regulators are used for controlling the pH of foods for stability or to affect activity of enzymes.
Anticaking agents
Anticaking agents keep powders such as milk powder from caking or sticking.
Antifoaming and foaming agents
Antifoaming agents reduce or prevent foaming in foods. Foaming agents do the reverse.
Antioxidants
Antioxidants such as vitamin C are preservatives by inhibiting the degradation of food by oxygen.

Bulking agents
Bulking agents such as starch are additives that increase the bulk of a food without affecting its taste.
Food coloring
Colorings are added to food to replace colors lost during preparation or to make food look more attractive.
Fortifying agents
Vitamins, minerals, and dietary supplements to increase the nutritional value
Color retention agents
In contrast to colorings, color retention agents are used to preserve a food's existing color.
Emulsifiers
Emulsifiers allow water and oils to remain mixed together in an emulsion, as in mayonnaise, ice cream, and homogenized milk.
Flavorings*
Flavorings are additives that give food a particular taste or smell, and may be derived from natural ingredients or created artificially.
*In EU, flavorings do not have an E-code and they are not considered as food additives.
Flavor enhancers
Flavor enhancers enhance a food's existing flavors. A popular example is monosodium glutamate. Some flavor enhancers have their own flavors that are independent of the food.
Flour treatment agents
Flour treatment agents are added to flour to improve its color or its use in baking.
Glazing agents
Glazing agents provide a shiny appearance or protective coating to foods.
Humectants
Humectants prevent foods from drying out.
Tracer gas
Tracer gas allows for package integrity testing to prevent foods from being exposed to atmosphere, thus guaranteeing shelf life.
Preservatives
Preservatives prevent or inhibit spoilage of food due to fungi, bacteria and other microorganisms.
Stabilizers
Stabilizers, thickeners and gelling agents, like agar or pectin (used in jam for example) give foods a firmer texture. While they are not true emulsifiers, they help to stabilize emulsions.
Sweeteners
Sweeteners are added to foods for flavoring. Sweeteners other than sugar are added to keep the food energy (calories) low, or because they have beneficial effects regarding diabetes mellitus, tooth decay, or diarrhea.
Thickeners
Thickening agents are substances which, when added to the mixture, increase its viscosity without substantially modifying its other properties.
Packaging
Bisphenols, phthalates, and perfluoroalkyl chemicals (PFCs) are indirect additives used in manufacturing or packaging. In July 2018 the American Academy of Pediatrics called for more careful study of those three substances, along with nitrates and food coloring, as they might harm children during development. [6]

Safety and regulation

With the increasing use of processed foods since the 19th century, food additives are more widely used. Many countries regulate their use. For example, boric acid was widely used as a food preservative from the 1870s to the 1920s, [7] [8] but was banned after World War I due to its toxicity, as demonstrated in animal and human studies. During World War II, the urgent need for cheap, available food preservatives led to it being used again, but it was finally banned in the 1950s. [7] Such cases led to a general mistrust of food additives, and an application of the precautionary principle led to the conclusion that only additives that are known to be safe should be used in foods. In the United States, this led to the adoption of the Delaney clause, an amendment to the Federal Food, Drug, and Cosmetic Act of 1938, stating that no carcinogenic substances may be used as food additives. [9] However, after the banning of cyclamates in the United States and Britain in 1969, saccharin, the only remaining legal artificial sweetener at the time, was found to cause cancer in rats. [10] Widespread public outcry in the United States, partly communicated to Congress by postage-paid postcards supplied in the packaging of sweetened soft drinks, led to the retention of saccharin, despite its violation of the Delaney clause. [11] However, in 2000, saccharin was found to be carcinogenic in rats due only to their unique urine chemistry. [12] [13]

In 2007, Food Standards Australia New Zealand published an official shoppers' guidance with which the concerns of food additives and their labeling are mediated. [14] In the EU it can take 10 years or more to obtain approval for a new food additive. This includes five years of safety testing, followed by two years for evaluation by the European Food Safety Authority (EFSA) and another three years before the additive receives an EU-wide approval for use in every country in the European Union. [15] Apart from testing and analyzing food products during the whole production process to ensure safety and compliance with regulatory standards, Trading Standards officers (in the UK) protect the public from any illegal use or potentially dangerous mis-use of food additives by performing random testing of food products. [16]

There has been significant controversy associated with the risks and benefits of food additives. [17] Natural additives may be similarly harmful or be the cause of allergic reactions in certain individuals. For example, safrole was used to flavor root beer until it was shown to be carcinogenic. Due to the application of the Delaney clause, it may not be added to foods, even though it occurs naturally in sassafras and sweet basil. [18]

Hyperactivity

Periodically, concerns have been expressed about a linkage between additives and hyperactivity, [19] however "no clear evidence of ADHD was provided". [20]

Toxicity

In 2012, the EFSA proposed the tier approach to evaluate the potential toxicity of food additives. It is based on four dimensions: toxicokinetics (absorption, distribution, metabolism and excretion); genotoxicity; subchronic (at least 90 data) and chronic toxicity and carcinogenity; reproductive and developmental toxicity. [21] Recent work has demonstrated that certain food additives such as carboxymethylcellulose may cause encroachment of microbes from the gastrointestinal tract into the protective mucus layer that lines the intestines. [22] Additional preclinical work suggests that emulsifiers may disrupt the gut microbiome, cause or exacerbate inflammation, and increase intestinal permeability. [23] Other food additives in processed foods, such as xanthan gum, have also been shown to influence the ecology of human gut microbiomes and may play a role in the divergence of gut microbiomes in industrialized societies as compared to pre-industrialized societies. [24] Although still controversial, some scientists hypothesize that these changes to human gut microbiomes may be a contributing factor to the rise in chronic inflammatory diseases in industrialized populations. [25]

Micronutrients

A subset of food additives, micronutrients added in food fortification processes preserve nutrient value by providing vitamins and minerals to foods such as flour, cereal, margarine and milk which normally would not retain such high levels. [26] Added ingredients, such as air, bacteria, fungi, and yeast, also contribute manufacturing and flavor qualities, and reduce spoilage. [27]

Approval in the United States

The United States Food and Drug Administration (FDA) defines a food additive as "any substance the intended use of which results or may reasonably be expected to result directly or indirectly in its becoming a component or otherwise affecting the characteristics of any food". [28] In order for a novel food additive to be approved in the U.S., a food additive approval petition (FAP) must be submitted to the FDA. [29] The identity of the ingredient, the proposed use in the food system, the technical effect of the ingredient, a method of analysis for the ingredient in foods, information on the manufacturing process, and full safety reports must be defined in a FAP. [30] For FDA approval of a FAP, the FDA evaluates the chemical composition of the ingredient, the quantities that would be typically consumed, acute and chronic health impacts, and other safety factors. [28] The FDA reviews the petition prior to market approval of the additive.[ citation needed ]

Standardization of its derived products

ISO has published a series of standards regarding the topic and these standards are covered by ICS 67.220. [31]

See also

Related Research Articles

<span class="mw-page-title-main">Aspartame</span> Artificial non-saccharide sweetener

Aspartame is an artificial non-saccharide sweetener 200 times sweeter than sucrose and is commonly used as a sugar substitute in foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide with brand names NutraSweet, Equal, and Canderel. Aspartame was approved by the US Food and Drug Administration (FDA) in 1974, and then again in 1981, after approval was revoked in 1980.

<span class="mw-page-title-main">Flavoring</span> Food additive used to change its aroma or taste

A flavoring, also known as flavor or flavorant, is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemoreceptors of the gustatory and olfactory systems. Along with additives, other components like sugars determine the taste of food.

A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by undesirable chemical changes. In general, preservation is implemented in two modes, chemical and physical. Chemical preservation entails adding chemical compounds to the product. Physical preservation entails processes such as refrigeration or drying. Preservative food additives reduce the risk of foodborne infections, decrease microbial spoilage, and preserve fresh attributes and nutritional quality. Some physical techniques for food preservation include dehydration, UV-C radiation, freeze-drying, and refrigeration. Chemical preservation and physical preservation techniques are sometimes combined.

<span class="mw-page-title-main">Sucralose</span> Non-nutritive sweetener

Sucralose is an artificial sweetener and sugar substitute. As the majority of ingested sucralose is not metabolized by the body, it adds no calories. In the European Union, it is also known under the E number E955. It is produced by chlorination of sucrose, selectively replacing three of the hydroxy groups—in the C1 and C6 positions of the fructose portion and the C4 position of the glucose portion—to give a 1,6-dichloro-1,6-dideoxyfructose–4-chloro-4-deoxygalactose disaccharide. Sucralose is about 600 times sweeter than sucrose, three times as sweet as both aspartame and acesulfame potassium, and twice as sweet as sodium saccharin.

<span class="mw-page-title-main">Sugar substitute</span> Sugarless food additive intended to provide a sweet taste

A sugar substitute is a food additive that provides a sweetness like that of sugar while containing significantly less food energy than sugar-based sweeteners, making it a zero-calorie or low-calorie sweetener. Artificial sweeteners may be derived through manufacturing of plant extracts or processed by chemical synthesis. Sugar substitute products are commercially available in various forms, such as small pills, powders, and packets.

<span class="mw-page-title-main">Disodium inosinate</span> Chemical compound

Disodium inosinate (E631) is the disodium salt of inosinic acid with the chemical formula C10H11N4Na2O8P. It is used as a food additive and often found in instant noodles, potato chips, and a variety of other snacks.

<span class="mw-page-title-main">Cyclamate</span> Chemical compound

Cyclamate is an artificial sweetener. It is 30–50 times sweeter than sucrose, making it the least potent of the commercially used artificial sweeteners. It is often used with other artificial sweeteners, especially saccharin; the mixture of 10 parts cyclamate to 1 part saccharin is common and masks the off-tastes of both sweeteners. It is less expensive than most sweeteners, including sucralose, and is stable under heating. Safety concerns led to it being banned in a few countries, though the European Union considers it safe.

<span class="mw-page-title-main">Neohesperidin dihydrochalcone</span> Chemical compound

Neohesperidin dihydrochalcone, sometimes abbreviated to neohesperidin DC or simply NHDC, is an artificial sweetener derived from citrus.

<span class="mw-page-title-main">Saccharin</span> Chemical compound

Saccharin, also called saccharine or benzosulfimide, or used in saccharin sodium or saccharin calcium forms, is a non-nutritive artificial sweetener. Saccharin is a benzoic sulfimide that is about 500 times sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products, such as drinks, candies, baked goods, tobacco products, excipients, and for masking the bitter taste of some medicines. It appears as white crystals and is odorless.

<span class="mw-page-title-main">Acesulfame potassium</span> Calorie-free sugar substitute

Acesulfame potassium, also known as acesulfame K or Ace K, is a synthetic calorie-free sugar substitute often marketed under the trade names Sunett and Sweet One. In the European Union, it is known under the E number E950. It was discovered accidentally in 1967 by German chemist Karl Clauss at Hoechst AG. In chemical structure, acesulfame potassium is the potassium salt of 6-methyl-1,2,3-oxathiazine-4(3H)-one 2,2-dioxide. It is a white crystalline powder with molecular formula C
4
H
4
KNO
4
S
and a molecular weight of 201.24 g/mol.

<span class="mw-page-title-main">Brominated vegetable oil</span> Type of vegetable oil used in the soft drinks industry

Brominated vegetable oil (BVO) is a complex mixture of plant-derived triglycerides that have been modified by atoms of the element bromine bonded to the fat molecules. Brominated vegetable oil is used to help emulsify citrus-flavored soft drinks, preventing them from separating during distribution. Brominated vegetable oil has been used by the soft drink industry since 1931, generally at a level of about 8 ppm.

<span class="mw-page-title-main">Diet soda</span> Type of sugar-free or artificially sweetened soda

Diet or light beverages are generally sugar-free, artificially sweetened beverages with few or no calories. They are marketed for diabetics and other people who want to reduce their sugar and/or caloric intake.

<span class="mw-page-title-main">Fumaric acid</span> Organic compound

Fumaric acid is an organic compound with the formula HO2CCH=CHCO2H. A white solid, fumaric acid occurs widely in nature. It has a fruit-like taste and has been used as a food additive. Its E number is E297. The salts and esters are known as fumarates. Fumarate can also refer to the C
4
H
2
O2−
4
ion (in solution). Fumaric acid is the trans isomer of butenedioic acid, while maleic acid is the cis isomer.

<span class="mw-page-title-main">Diet Pepsi</span> Sugar-free, artificially sweetened soda

Diet Pepsi is a diet carbonated cola soft drink produced by PepsiCo, introduced in 1964 as a variant of Pepsi with no sugar. First test marketed in 1963 under the name Patio Diet Cola, it was re-branded as Diet Pepsi the following year, becoming the first diet cola to be distributed on a national scale in the United States. In the 1960s and 1970s, its competition consisted of the Coca-Cola Company's subsequently discontinued Tab. The United States represents the largest single market for Diet Pepsi.

<span class="mw-page-title-main">Liquid smoke</span> Edible chemical compound

Liquid smoke is a water-soluble yellow to red liquid used as a flavoring as a substitute for cooking with wood smoke while retaining a similar flavor. It can be used to flavor any meat or vegetable. It is available as pure condensed smoke from various types of wood, and as derivative formulas containing additives.

<span class="mw-page-title-main">Natural food</span> Food labeling and marketing term

Natural food and all-natural food are terms in food labeling and marketing with several definitions, often implying foods that are not manufactured by processing. In some countries like the United Kingdom, the term "natural" is defined and regulated; in others, such as the United States, the term natural is not enforced for food labels, although there is USDA regulation of organic labeling.

<span class="mw-page-title-main">Glutamate flavoring</span> Generic name for flavor-enhancing compounds based on glutamic acid and its salts

Glutamate flavoring is the generic name for flavor-enhancing compounds based on glutamic acid and its salts (glutamates). These compounds provide an umami (savory) taste to food.

<span class="mw-page-title-main">Saccharin Study and Labeling Act of 1977</span> US law

Saccharin Study and Labeling Act of 1977 or Saccharin Study, Labeling and Advertising Act was a United States federal statute enacting requirements for a scientific observation regarding the impurities in, potential toxicity, and problematic carcinogenicity of a non-nutritive sweetener better known as saccharin. The Act of Congress invoked an immediate eighteen month moratorium prohibiting the Secretary of Health, Education, and Welfare from pursuing regulatory implications by limiting the production and use of saccharin. The Act codified a warning label requirement advocating the non-nutritive sweetener had been discovered to yield carcinogenicity in laboratory animals.

The Food Chemicals Codex (FCC) is a collection of internationally recognized standards for the purity and identity of food ingredients.

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Additional sources